Co-dfns is Open Source, and funded/licensed by Dyalog. They also produce MiServer and a host of tools Open Source as well. The problem is that they have to fund that work somehow, and I've yet to see a good business model on interpreters and compilers for Open Source that works well enough for Dyalog to take the risk. If I can successfully market and fund Co-dfns through an Open community funding model, I think it would go a long way towards encouraging Dyalog in openness (they are already quite open to it).

Dyalog does have a Windows windowing environment, but also their web framework, for designing interfaces. They are actively working to improve their cross-platform situation, with things like RIDE, MiServer, and the like.

As long as you can live without the GUI elements of plotting, you can use the shipped Plotting and Documentation tools (SharpPlot?) that gives you graphing and plotting tools, and produces images that you can open in a viewer. This is what I use when generating graphs and plots on Linux. SharpPlot or the Plot Wizard is very nice on the Windows IDE, but the purely command line version works great on Linux and Mac.

Cross platform GUI applications for Dyalog are best done either with individually coded backends or making it a hosted web application through the MiServer Web Framework, which has some support for doing this.

Open source is a chicken-and-egg problem. If you want success stories, look at c/c++/fortran/perl/python/R/julia, old and new. I don't have a solution. I just blame IBM and all others who monetized on APL in a short dozen years and didn't manage to hold their ground.

In an alternate universe we would see current fortran users writing APL.

More realistically, had anyone write an APL compiler that gets some applications to run on any of the top 50 supercomputers with even one percent of its peak performance, APL would still have a chance.

I also don't know if I would consider C/C++ or Python or the others success stories. They all have an ecosystem around them that allows for developers to be funded doing work on these projects, but only because of other products that are out there. Other products produce money, and are making enough to allow some companies and individuals to fund core technology improvements. That's different and a harder model to work with, because it requires massive scale to be effective.

APL had 50 years.

Julia had 5.

We're working on it! We're getting close already. If you have a naively parallel algorithm that is good for doing CSP style decompositions on, then you can compile your individual unit programs using Co-dfns and then using Dyalog APL Isolates to distribute the bulk computation across the distributed computing cloud. It's more work than it should be right now, but it does work for the right types of problems.

One problem with cross-platform graphical environments, IMO, are that they fail the integration standards that I've come to expect from GUI apps. I want Mac apps to feel like Mac apps, Linux apps like Linux apps, and Windows apps like Windows apps. This means making heavy use of specific interaction paradigms for each platform to achieve the best level of integration. This isn't possible with shared graphical environments.

I think this expectation has mostly dropped away in the last couple years. A lot of apps now have interfaces inspired by apps (e.g. Airmail on Mac OS X acts like an iPad app) or web apps (all the Electron apps). Obviously this isn't saying that a personal dislike for it is wrong, I just think that it's becoming less important in the market.

This might be true for standard consumer applications that can fit within the web paradigm. However, you then fail to be able to leverage vendor specific interaction paradigms, which is something I want to be able to do, such as the Mac touch strip, the Windows Surface Dial and Pen, or the Gnome title bar/notifications/messaging interface. I like to interact with voice services, so you need something for this as well, or handling the various HiDPI features of each system.

RIDE is already quite good. It is simple and effective and in a sense better than jupyter. Throw in some D3 they would get the graphical capabilities, just like how jhs does it.

A comercial example? Mathematica.

Imagine a Mathematica clone with APL...

I'm actually designing one better. :-) Probably a few years out from true production ready (maybe more, who am I kidding, probably more), but definition something cool.